J
James
- Jan 1, 1970
- 0
I am having a problem controlling an H-Bridge Circuit that I put
together, it is a variant of Eugene Blanchard's design. Anyway the
schematic can be found here:
http://www.geocities.com/jj_legend_83/circuit.jpg
I two power supplies, one of the driving voltage, and one for the power
to the gates of the MOSFETs. I have a function generator as a logical
input to the circuitry. The voltages that are involved are on the
circuit diagram. I have the grounds of the two bottom MOSFETs attached
to the negative terminal of the driving voltage DC power supply, and
the rest of the grounds are attached to the negative terminal of the
control voltage power supply. The floating terminal of the function
generator is also attached to the negative terminal of the control
voltage power supply.
Anyway, the upper-left BJT and MOSFET are always "on", and I am having
trouble figuring out why. If anybody could give me some pointers here
that would be great. Thanks!
- James
together, it is a variant of Eugene Blanchard's design. Anyway the
schematic can be found here:
http://www.geocities.com/jj_legend_83/circuit.jpg
I two power supplies, one of the driving voltage, and one for the power
to the gates of the MOSFETs. I have a function generator as a logical
input to the circuitry. The voltages that are involved are on the
circuit diagram. I have the grounds of the two bottom MOSFETs attached
to the negative terminal of the driving voltage DC power supply, and
the rest of the grounds are attached to the negative terminal of the
control voltage power supply. The floating terminal of the function
generator is also attached to the negative terminal of the control
voltage power supply.
Anyway, the upper-left BJT and MOSFET are always "on", and I am having
trouble figuring out why. If anybody could give me some pointers here
that would be great. Thanks!
- James